Effect of KBrO3 on Gel-forming Properties of Walleye Pollack Surimi through Setting with or without Transglutaminase Inhibitor

Abstract

In order to clarify the effect of oxidation itself on the gel formation of salted-surimi through setting, the gel-forming properties were examined with or without transglutaminase (TGase) inhibitor. The gels were prepared from walleye pollack salted-surimi mixed with KBrO3 through setting at 30 degrees C (suwari gel) for 2 h prior to heating at 80 degrees C for 20 min (kamaboko gel) in the presence or absence of TGase inhibitor. The gel strength of kamaboko gel increased through setting but KBrO3 almost did not promote the gel formation of kamaboko gels through setting comparing with control. KBrO3 increased the breaking strength and decreased elongation so that the gel became harder. Even in the presence of TGase inhibitor, where the increase in gel strength during setting was suppressed, KBrO3 showed the promotion of gel formation, although the gel strength is lower than the gel without TGase inhibitor. Almost, similar behaviors of protein polymerization by disulfide bonds and the oxidation of sulfhydryl groups to those in the absence of TGase inhibitor were observed. These results suggest that KBrO3 enhances the gel forming ability of walleye pollack surimi through the disulfide bonding of myosin heavy chain by oxidation during the setting. In conclusion, the oxidation of salted surimi sol during setting at 30 degrees C can contribute to the gel formation, but its contribution seems not to be cooperative with that of TGase.